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The increasing global commitment to carbon neutrality has propelled a heightened focus on sustainable construction materials, with wood emerging as pivotal due to its environmental benefits. This review explores the development and application of eco-friendly polymer nanocomposite coatings to enhance wood’s fire resistance, addressing a critical limitation in its widespread adoption. These nanocomposites demonstrate improved thermal stability and char formation properties by integrating nanoparticles, such as nano-clays, graphene oxide, and metal oxides, into biopolymer matrices. This significantly mitigates the flammability of wood substrates, creating a robust barrier against heat and oxygen. The review provides a comprehensive examination of these advanced coatings’ synthesis, characterization, and performance. By emphasizing recent innovations and outlining future research directions, this review underscores the potential of eco-friendly polymer nanocomposite coatings as next-generation fire retardants. This advancement supports the expanded utilization of wood in sustainable construction practices and aligns with global initiatives toward achieving carbon neutrality.

The addition of nanostructures to polymeric materials allows for a direct interaction between polymeric chains and nanometric structures, resulting in a synergistic process through the physical (electrostatic forces) and chemical properties (bond formation) of constituents for the modification of their properties and potential cutting-edge materials. This study explores a novel in situ synthesis method for PDMS-%SiO2 nanoparticle composites with varying crosslinking degrees (PDMS:TEOS of 15:1, 10:1, and 5:1); particle concentrations (5%, 10%, and 15%); and sol-gel catalysts (acidic and alkaline). This investigation delves into the distinct physical and chemical properties of silicon nanoparticles synthesized under acidic (SiO2-a) and alkaline (SiO2-b) conditions. A characterization through Raman, FT-IR, and XPS analyses confirms particle size and agglomeration differences between both the SiO2-a and SiO2-b particles. Similar chemical environments, with TEOS and ethanol by-products, were detected for both systems. The results on polymer composites elucidate the successful incorporation of SiO2 nanoparticles into the PDMS matrix without altering the PDMS’s chemical structure. However, the presence of nanoparticles did affect the relative intensities of specific vibrational modes over composites from −35% to 24% (Raman) and from −14% to 59% (FT-IR). The XPS results validate the presence of Si, O, and C in all composites, with significant variations in atomic proportions (C/Si and O/Si) and Si and C component analyses through deconvolution techniques. This study demonstrates the successful in situ synthesis of PDMS-SiO2 composites with tunable properties by controlling the sol-gel and crosslinking synthesis parameters. The findings provide valuable insights into the in situ synthesis methods of polymeric composite materials and their potential integration with polymer nanocomposite processing techniques.

This study investigates the osteogenic differentiation of umbilical-cord-derived human mesenchymal stromal cells (hUC-MSCs) on biphasic calcium phosphate (BCP) scaffolds derived from cuttlefish bone doped with metal ions and coated with polymers. First, the in vitro cytocompatibility of the undoped and ion-doped (Sr2+, Mg2+ and/or Zn2+) BCP scaffolds was evaluated for 72 h using Live/Dead staining and viability assays. From these tests, the most promising composition was found to be the BCP scaffold doped with strontium (Sr2+), magnesium (Mg2+) and zinc (Zn2+) (BCP-6Sr2Mg2Zn). Then, samples from the BCP-6Sr2Mg2Zn were coated with poly(ԑ-caprolactone) (PCL) or poly(ester urea) (PEU). The results showed that hUC-MSCs can differentiate into osteoblasts, and hUC-MSCs seeded on the PEU-coated scaffolds proliferated well, adhered to the scaffold surfaces, and enhanced their differentiation capabilities without negative effects on cell proliferation under in vitro conditions. Overall, these results suggest that PEU-coated scaffolds are an alternative to PCL for use in bone regeneration, providing a suitable environment to maximally induce osteogenesis.

The increasing global commitment to carbon neutrality has propelled a heightened focus on sustainable construction materials, with wood emerging as pivotal due to its environmental benefits. This review explores the development and application of eco-friendly polymer nanocomposite coatings to enhance wood's fire resistance, addressing a critical limitation in its widespread adoption. These nanocomposites demonstrate improved thermal stability and char formation properties by integrating nanoparticles, such as nano-clays, graphene oxide, and metal oxides, into biopolymer matrices. This significantly mitigates the flammability of wood substrates, creating a robust barrier against heat and oxygen. The review provides a comprehensive examination of these advanced coatings' synthesis, characterization, and performance. By emphasizing recent innovations and outlining future research directions, this review underscores the potential of eco-friendly polymer nanocomposite coatings as next-generation fire retardants. This advancement supports the expanded utilization of wood in sustainable construction practices and aligns with global initiatives toward achieving carbon neutrality.

A solvent-free route of initiated chemical vapor deposition (iCVD) was used to synthesize a bio-renewable poly(α-Methylene-γ-butyrolactone) (PMBL) polymer. α-MBL, also known as tulipalin A, is a bio-based monomer that can be a sustainable alternative to produce polymer coatings with interesting material properties. The produced polymers were deposited as thin films on three different types of substrates—polycarbonate (PC) sheets, microscopic glass, and silicon wafers—and characterized via an array of characterization techniques, including Fourier-transform infrared (FTIR), proton nuclear magnetic resonance spectroscopy (1H NMR), ultraviolet visible spectroscopy (UV–vis), differential scanning calorimetry (DSC), size-exclusion chromatography (SEC), and thermogravimetric analysis (TGA). Optically transparent thin films and coatings of PMBL were found to have high thermal stability up to 310 °C. The resulting PMBL films also displayed good optical characteristics, and a high glass transition temperature (Tg~164 °C), higher than the Tg of its structurally resembling fossil-based linear analogue-poly(methyl methacrylate). The effect of monomer partial pressure to monomer saturation vapor pressure (Pm/Psat) on the deposition rate was investigated in this study. Both the deposition rate and molar masses increased linearly with Pm/Psat following the normal iCVD mechanism and kinetics that have been reported in literature.

To address the challenging issues of metal materials corrosion in industries, which has caused huge economic losses and security threats to many facilities in marine environments, functional polymer coatings have been widely used and regarded as one of the simplest and most effective methods to prevent such an undesirable event. In this study, a new type of coating filler consisting of graphene oxide/polyaniline/polydopamine (GO-PANI-PDA) nanocomposites has been successfully synthesized. The morphology, structure, composition, and corrosion resistance performance of the GO-PANI-PDA (GPP) nanocomposites were investigated via a series of characterization methods. The results from our electrochemical impedance spectroscopy, potentiodynamic polarization curve and salt spray experiment showed that the best corrosion resistance performance of the coating is from GPP 21 with the epoxy/GO-PANI:PDA ratio of 2:1, which exhibited a positive corrosion potential (−0.51 V) shift from epoxy/GO-PANI coating (−0.64 V). The corrosion current density (3.83 × 10−8 A/cm2) of GPP 21 is nearly an order of magnitude lower than that of epoxy/GO-PANI (7.05 × 10−7 A/cm2). The good anti-corrosion performance was fascinatingly observed in salt spray tests even without obvious corrosion phenomenon after 30 days of testing. Due to these remarkable properties, GPP nanocomposites can be an outstanding candidate for the rapid development of broadband shielding and anticorrosive materials.

The addition of nanostructures to polymeric materials allows for a direct interaction between polymeric chains and nanometric structures, resulting in a synergistic process through the physical (electrostatic forces) and chemical properties (bond formation) of constituents for the modification of their properties and potential cutting-edge materials. This study explores a novel in situ synthesis method for PDMS-%SiO 2 nanoparticle composites with varying crosslinking degrees (PDMS:TEOS of 15:1, 10:1, and 5:1); particle concentrations (5%, 10%, and 15%); and sol-gel catalysts (acidic and alkaline). This investigation delves into the distinct physical and chemical properties of silicon nanoparticles synthesized under acidic (SiO 2 -a) and alkaline (SiO 2 -b) conditions. A characterization through Raman, FT-IR, and XPS analyses confirms particle size and agglomeration differences between both the SiO 2 -a and SiO 2 -b particles. Similar chemical environments, with TEOS and ethanol by-products, were detected for both systems. The results on polymer composites elucidate the successful incorporation of SiO 2 nanoparticles into the PDMS matrix without altering the PDMS's chemical structure. However, the presence of nanoparticles did affect the relative intensities of specific vibrational modes over composites from -35% to 24% (Raman) and from -14% to 59% (FT-IR). The XPS results validate the presence of Si, O, and C in all composites, with significant variations in atomic proportions (C/Si and O/Si) and Si and C component analyses through deconvolution techniques. This study demonstrates the successful in situ synthesis of PDMS-SiO 2 composites with tunable properties by controlling the sol-gel and crosslinking synthesis parameters. The findings provide valuable insights into the in situ synthesis methods of polymeric composite materials and their potential integration with polymer nanocomposite processing techniques.

Icephobic coatings interest various industries facing icing problems. However, their durability represents a current limitation in real applications. Therefore, understanding the degradation of coatings under various environmental stresses is necessary for further coating development. Here, lubricated icephobic coatings were fabricated using a flame spray method with hybrid feedstock injection. Low-density polyethylene represented the main coating component. Two additives, namely fully hydrogenated cottonseed oil and paraffinic wax, were added to the coating structure to enhance coating icephobicity. Coating properties were characterised, including topography, surface roughness, thermal properties, wettability, and icephobicity. Moreover, their performance was investigated under various environmental stresses, such as repeated icing/deicing cycles, immersion in corrosive media, and exposure to ultraviolet (UV) irradiation. According to the results, all coatings exhibited medium-low ice adhesion, with slightly more stable icephobic behaviour for cottonseed oil-based coatings over the icing/deicing cycles. Surface roughness slightly increased, and wetting performances decreased after the cyclic tests, but chemical changes were not revealed. Moreover, coatings demonstrated good chemical resistance in selected corrosive media, with better performance for paraffin-based coatings. However, a slight decrease in hydrophobicity was detected due to surface structural changes. Finally, paraffin-based coatings showed better resistance under UV irradiation based on carbonyl index and colour change measurements.

This study investigates the osteogenic differentiation of umbilical-cord-derived human mesenchymal stromal cells (hUC-MSCs) on biphasic calcium phosphate (BCP) scaffolds derived from cuttlefish bone doped with metal ions and coated with polymers. First, the in vitro cytocompatibility of the undoped and ion-doped (Sr 2+ , Mg 2+ and/or Zn 2+ ) BCP scaffolds was evaluated for 72 h using Live/Dead staining and viability assays. From these tests, the most promising composition was found to be the BCP scaffold doped with strontium (Sr 2+ ), magnesium (Mg 2+ ) and zinc (Zn 2+ ) (BCP-6Sr2Mg2Zn). Then, samples from the BCP-6Sr2Mg2Zn were coated with poly(ԑ-caprolactone) (PCL) or poly(ester urea) (PEU). The results showed that hUC-MSCs can differentiate into osteoblasts, and hUC-MSCs seeded on the PEU-coated scaffolds proliferated well, adhered to the scaffold surfaces, and enhanced their differentiation capabilities without negative effects on cell proliferation under in vitro conditions. Overall, these results suggest that PEU-coated scaffolds are an alternative to PCL for use in bone regeneration, providing a suitable environment to maximally induce osteogenesis.

A solvent-free route of initiated chemical vapor deposition (iCVD) was used to synthesize a bio-renewable poly(α-Methylene-γ-butyrolactone) (PMBL) polymer. α-MBL, also known as tulipalin A, is a bio-based monomer that can be a sustainable alternative to produce polymer coatings with interesting material properties. The produced polymers were deposited as thin films on three different types of substrates-polycarbonate (PC) sheets, microscopic glass, and silicon wafers-and characterized via an array of characterization techniques, including Fourier-transform infrared (FTIR), proton nuclear magnetic resonance spectroscopy ( 1 H NMR), ultraviolet visible spectroscopy (UV-vis), differential scanning calorimetry (DSC), size-exclusion chromatography (SEC), and thermogravimetric analysis (TGA). Optically transparent thin films and coatings of PMBL were found to have high thermal stability up to 310 °C. The resulting PMBL films also displayed good optical characteristics, and a high glass transition temperature ( T g ~164 °C), higher than the T g of its structurally resembling fossil-based linear analogue-poly(methyl methacrylate). The effect of monomer partial pressure to monomer saturation vapor pressure ( P m /P sat ) on the deposition rate was investigated in this study. Both the deposition rate and molar masses increased linearly with Pm/Psat following the normal iCVD mechanism and kinetics that have been reported in literature.

To address the challenging issues of metal materials corrosion in industries, which has caused huge economic losses and security threats to many facilities in marine environments, functional polymer coatings have been widely used and regarded as one of the simplest and most effective methods to prevent such an undesirable event. In this study, a new type of coating filler consisting of graphene oxide/polyaniline/polydopamine (GO-PANI-PDA) nanocomposites has been successfully synthesized. The morphology, structure, composition, and corrosion resistance performance of the GO-PANI-PDA (GPP) nanocomposites were investigated via a series of characterization methods. The results from our electrochemical impedance spectroscopy, potentiodynamic polarization curve and salt spray experiment showed that the best corrosion resistance performance of the coating is from GPP 21 with the epoxy/GO-PANI:PDA ratio of 2:1, which exhibited a positive corrosion potential (-0.51 V) shift from epoxy/GO-PANI coating (-0.64 V). The corrosion current density (3.83 × 10 -8 A/cm 2 ) of GPP 21 is nearly an order of magnitude lower than that of epoxy/GO-PANI (7.05 × 10 -7 A/cm 2 ). The good anti-corrosion performance was fascinatingly observed in salt spray tests even without obvious corrosion phenomenon after 30 days of testing. Due to these remarkable properties, GPP nanocomposites can be an outstanding candidate for the rapid development of broadband shielding and anticorrosive materials.

Icephobic coatings interest various industries facing icing problems. However, their durability represents a current limitation in real applications. Therefore, understanding the degradation of coatings under various environmental stresses is necessary for further coating development. Here, lubricated icephobic coatings were fabricated using a flame spray method with hybrid feedstock injection. Low-density polyethylene represented the main coating component. Two additives, namely fully hydrogenated cottonseed oil and paraffinic wax, were added to the coating structure to enhance coating icephobicity. Coating properties were characterised, including topography, surface roughness, thermal properties, wettability, and icephobicity. Moreover, their performance was investigated under various environmental stresses, such as repeated icing/deicing cycles, immersion in corrosive media, and exposure to ultraviolet (UV) irradiation. According to the results, all coatings exhibited medium-low ice adhesion, with slightly more stable icephobic behaviour for cottonseed oil-based coatings over the icing/deicing cycles. Surface roughness slightly increased, and wetting performances decreased after the cyclic tests, but chemical changes were not revealed. Moreover, coatings demonstrated good chemical resistance in selected corrosive media, with better performance for paraffin-based coatings. However, a slight decrease in hydrophobicity was detected due to surface structural changes. Finally, paraffin-based coatings showed better resistance under UV irradiation based on carbonyl index and colour change measurements.